Method For Producing Sterol Formulations

ABSTRACT

The invention relates to a wet grinding method for producing sterol formulations having good wettability. According to said method, a) an additive selected from the group constituted by proteins, proteinaceous adjuvants, carbohydrates, cellulose derivatives, sugar alcohols, fruit concentrates and vegetable concentrates is dissolved or dispersed in water or in an aqueous suspension medium, b) sterol and/or stanol particles having a medium particle size of at least 1 mm are added to this solution/dispersion, c) the dispersion thus obtained is homogenized and size-reduced in a mill that works according to the rotor/stator principle, and d) is then optionally dried, with the proviso that the sterol and/or stanol particles are present in the final formulation with a particle size distribution of D 90%  of not more than 50 μm. Owing to their good wettability, the sterol-containing formulations produced according to this method can be incorporated into food items without complex technology and have good organoleptic and sensory properties especially when used in drinks and dairy products.

FIELD OF THE INVENTION

The invention is in the field of foods and relates to a method ofproducing readily wettable phytosterol-containing formulations, thepreparations produced according to this method, and also products, inparticular foods, which contain these formulations.

PRIOR ART

Numerous possible methods of formulation are known from applicationtechnology for being able to incorporate slightly water-solublephytosterols and phytostanols which are used as cholesterol-loweringagents into food preparations or pharmaceutical products.

Numerous patent applications describe how the availability of sterolscan be improved via reducing particle sizes, principally bymicronization. For instance, German laid-open application DE 102 53 111A1 describes pulverulent phytosterol formulations having a medianparticle size of 0.01 to 100 μm which may be readily redispersed inwater. Preferably, use is made of hydrophilic auxiliaries as protectivecolloids. For producing the powders, use is made of organic solvents tothe disadvantage of ecology and acceptability. International applicationWO 2005/074717 A1 also uses a type of protective colloid by embeddingsterols into a matrix which contains proteins and carbohydrates. Thetotal sterol content in the formulation, however, is small, owing to thehigh fraction of auxiliaries.

A further method for producing a sterol dispersion in which the particlesize distribution of the sterols is from 0.1 to 30 μm, may be found inthe international applications WO 03/105611 and WO 2005/049037. As inthis method, frequently micronization of the sterol particles alone isinsufficient in order to achieve good incorporability. Although thebioavailability of the finely dispersed particles may be improved byincreasing the surface area, especially the micronized particles arepoorly wettable, aggregate readily and generally float on aqueoussurfaces. Frequently, the ground sterol can only be dispersed in a drinkusing special methods, for which intense mixing is necessary. However,these apparatuses are not usually available to the end user, the foodmanufacturer.

Therefore, many manufacturers combine micronization of sterols with theadditional use of emulsifiers. An example thereof are the preparationsclaimed in European patent EP 0897671 B1 having sterols and sterolesters having a particle size of a maximum of 15 μm in a mixture withselected emulsifiers, wherein the weight ratio of emulsifier to sterolin the aqueous phase is less than 1:2.

In the international patent application WO 03/086468 A1, pulverulentsterol ester formulations having a low protein content and mono- anddiglycerides as emulsifiers are disclosed. Even if these aredistinguished by good acceptability and have already been known as foodemulsifiers over a long time period, attempts are made to decrease theamount of the emulsifiers, or even to avoid them completely, sinceemulsifiers also affect the bioavailability of other substances presentin the foods or can adversely affect the stability of the formulations.

Other methods of improving the solubility and dispersibility, such asformulation as emulsions, microemulsions, dispersions, suspensions orcomplexing with cyclodextrins or bile salts are presented ininternational patent application WO 99/63841 A1. Proposed supports arePEG, PVP, copolymers, cellulose ethers and cellulse esters. Also, directuse of food base materials as supports for pulverized sterols in theform of a premix is disclosed by EP 1 003 388 B1. The selection ofproteins as support substances for non-esterified sterols and stanols isdisclosed in WO 01/37681.

In particular, processing non-esterified sterols and stanols which arestill very much more hydrophobic than their esterified derivatives makeshigh demands on the production method. Free ground sterols in addition,have the disadvantage that they have a low minimum ignition energy(MIE<3 mJ), and therefore these products are categorized as extremelysensitive to ignition. Therefore, when free sterols are used,corresponding safety precautions must be heeded.

A possible method of producing sterol-containing microparticles can befound in European patent EP 1148793 B1. It is based on high-energyhomogenization. However, a powder produced thereby based on aqueoussuspension media has an inadequate homogeneity and can only beredispersed with difficulty. A disadvantage of many sterol-containingpowder formulations is the agglomeration behavior of the free sterols onstorage. During storage, especially if they are stored under pressure,severe clumping or lump formation is observed, and the soliduncontrolled agglomerates must again be comminuted in order then to beable to be processed.

In the international patent application WO 2006/020980 A1, agglomeratesof sterol particles are described. The production method is asize-enlargement granulation of adhesive granules in which themicronized sterol particles are wetted with a suspension medium in whicha binder is in part or completely dissolved. The suspension medium isremoved after the wetting, in such a manner that the remainingagglomerates have a size of 150 to 850 μm. This method requires a highuse of apparatus and must be controlled very precisely, in order thatthe agglomerates produced have the desired stability.

It was an object of the present invention to provide sterol-containingformulations having a high content of sterols and/or stanols, which maybe produced using simple and rapid processes, and enable good and rapiddispersion and incorporation of non-esterified sterols and/or stanols infoods, wherein the formulations should have good sensory andorganoleptic properties in the foods.

DESCRIPTION OF THE INVENTION

The invention relates to a wet grinding method for producing readilywettable sterol formulations, in which

a) an additive is selected from the group which is formed by proteins,protein-containing auxiliaries, carbohydrates, cellulose derivatives,sugar alcohols, fruit concentrates and vegetable concentrates dissolvedor dispersed in water or an aqueous suspension medium

b) to this solution/dispersion is added sterol particles and/or stanolparticles having a median particle size of at least 1 mm,

c) the resultant dispersion is homogenized and comminuted in a millwhich operates by the rotor-stator principle and

d) is if appropriate subsequently dried,

with the proviso that the sterol particles and/or stanol particles arepresent in the final formulation in a particle size distribution havinga D_(90%) of a maximum of 50 μm.

The method according to the invention enables powders also to beproduced with free non-esterified sterols and stanols which enable easyfurther processing of the the lipophilic active ingredients withoutgreat requirements of apparatus and at room temperature in foods, inparticular drinks. The powder has a low agglomeration tendency andtherefore good flow properties. It is distinguished by good homogeneityand, owing to its improved wettability, can be further processed withoutgreat technical resources, wherein a homogeneous distribution in thefinal formulation is also rapidly achieved. Owing to the coating of thesterol surface with the hydrophilic additives, the organolepticproperties and the sensory properties are decisively improved. Thecoated powder does not stick to teeth and oral mucosa, and therefore theunpleasant sterol taste which leads to considerable taste impairments infoods containing the active ingredients is completely suppressed.

By using hydrophilic additives such as proteins, protein-containingauxiliaries, carbohydrates, sugar alcohols, fruit concentrates andvegetable concentrates, not only are solubilization properties anddispersion properties improved, but surprisingly these powders alsoexhibit an increased storage stability compared with pure ground sterolswhich have a high agglomeration tendency.

The method allows organic solvents or heating the formulation to beavoided in the processing of non-esterified sterols and stanols, anddespite the aqueous medium, allows the omission of emulsifiers having ahigh surface activity, especially of the type of lecithins,monoglycerides, diglycerides, polysorbates, sodium stearyl lactylate,glycerol monostearate, lactic acid esters and polyglycerol esters. Thelow emulsifying properties of the hydrophilizing auxiliaries, inparticular the caseinates, the milk powder or the gum arabic aresufficient in order to ensure the homogeneity of the powder which isproduced and ready redispersibility and processability. The omission offurther emulsifiers simplifies the further processing by reducingpossible incompatibilities with other food constituents and decreasesthe occurrence of incompatibilities with the consumer.

A particular advantage of the method is carrying out grinding andcoating in one operating step. The use of the wet grinding method forcomminuting the sterol particles avoids the high risk of powderexplosions. The particle size of the sterols and/or stanols initiallyused is relatively high in order to avoid firstly powder explosions andsecondly to ensure good handling. Thus finished prills, which have avery high storage stability, can be used. Preferably, the mean particlesizes are greater than 1 mm. At this size, the particle sizedetermination is carried out by conventional sieve analysis. The sterolparticles and/or stanol particles in the final formulation are, afterthe wet grinding, present in a particle size distribution having aD_(90%) of a maximum of 50 μm, preferably a maximum of 40 μm, andparticularly preferably a maximum of 30 μm. The particle sizedistribution was determined using an instrument from

Beckman Coulter, type LS 230 and calculated as volume distribution. Themeasurement was performed in aqueous suspension.

In order to keep the processing requirement low, the time required forgrinding which leads to this degree of comminution should be a maximumof 2 hours, preferably a maximum of 1 hour. The process generallyproceeds at <2-3 bar (<43.5 psi). And pasty to compacted masses can alsobe processed.

The mill which is to be used in this case is based on a rotor-statorprinciple. Toothed colloid mills, but also Ultra-Turrax, corundum mills,perforated disk mills or ring ball mills in which the balls are situatedin the gap between rotor and housing, are suitable for the methodaccording to the invention. Toothed colloid mills have proved to beparticularly advantageous. On the basis of the observation that theenergy input on grinding must have a magnitude which firstly permitssufficient comminution without extreme heating of the material to beground and secondly should lead to a low charging of the particles,these mills have proved to be particularly suitable. Shearing forceswhich are exerted by high-performance mills, as are known from Europeanpatent EP 1148793 B1 for the comminution of sterols, are not acceptablefor good storage stability without clump formation of the particles.They have, in addition, proved to be disadvantageous for uniform surfacecoating by the hydrophilizing additives.

The expenditure on apparatus of the production equipment according tothe invention is therefore very low. Cooling of the material to beground during grinding can be omitted, the thermal stress of thematerial is low. In addition, the risk of dust explosions is reduced tovery low levels by the use of wet grinding.

It is possible by using the wet grinding method according to theinvention to produce powders having a very high sterol content havingthe above described advantageous properties, wherein the use of organicsolvents and heating of the sterol particles is avoided. The aqueousdispersions have concentrations of sterols and stanols of at least 20%by weight, preferably at least 30% by weight, and particularlypreferably at least 40% by weight, and especially at least 50% byweight, based on the total weight of the dispersion.

These dispersions are preferably dried. For this, the conventionaldrying methods such as vacuum drying or spray drying are suitable. Sincethe additives are only used for hydrophilization and the surfaces of thesterols are coated therewith, the total content of sterols in thepowders is very high. The powder resulting after drying actuallycontains at least 75% by weight, particularly preferably at least 85% byweight, and in particular at least 90% by weight of sterols and/orstanols, based on the weight of the dried powders.

Powders having sterol/stanol contents of at least 90% which may beproduced by this method are therefore—just on the basis of the sterolcontent—comparable with ground or micronized sterols/stanols. Comparedwith these ground or micronized sterols/stanols, the powders accordingto the invention, however, are distinguished by the followingadvantages: they are more free-flowing and may be easily dispersed inwater without applying high shear forces. Enterprises carrying outfurther processing such as, for example, dairies, can therefore usetheir routine agitators for incorporation into foods.

The good water dispersibility is surprising in that the amount ofsupport (max. 10%) at the particle size of a maximum of 50 μm is notsufficient to coat all particles (e.g.: if, for a 50 μm particle(surface area of 0.0079 mm²/particle) approximately 63% support isrequired in order to obtain a 10 μm thick coating; for 30 μm particlesthis is already around 78% of support material.

In addition, the powders may be stored without lump formation andcaking. Ground sterols have a very high tendency to caking. This leadsto the fact that after relatively long storage a block is obtained whichmust be comminuted by powerful application of force before it can beused. In addition, the storage becomes safer owing to the increasedminimum ignition energy. In the case of the ground sterols and stanols,this has a very low value of 1 mJ>MIE<3 mJ.

The preparations according to the invention are markedly safer here evenat a low amount of support (10%): 3 mJ>MIE<10 mJ.

The sterol content of the final formulation is dependent on the amountof the hydrophilic additive used. A weight ratio of additive to sterolfraction/stanol fraction of 1:3 to 1:20 is advantageous, preferably 1:9to 1:15, and particularly preferably to 1:14 to 1:16.

Also, compared with dispersions, the powders have the advantage that,firstly, the content of active substance is very much greater, thestorage stability is decisively improved and—especially in the case ofaqueous media—the microbiological stability is markedly increased.

Owing to the low fraction of support, only slight changes and effects ofthe final recipe are to be expected. This is in contrast to adispersion, for which the medium/matrix (oil, milk, fatty cream) has anot insignificant effect, owing to the high amount of matrix.

The sterol-containing formulations produced by these methods can beincorporated in a simple manner into foods, in particular into milks,milk drinks, whey drinks, yoghurt drinks, margarine, fruit juices, fruitjuice mixtures, fruit juice drinks, vegetable juices, carbonated andnon-carbonated drinks, soymilk drinks or protein-rich liquid foodreplacement drinks, and also fermented milk preparations, yoghurt,drinking yoghurt or cheese preparations, but also into pharmaceuticalpreparations.

If the additive used is fruit concentrate or vegetable concentrate, twomethod variants are possible: in one variant the fruit concentrate orvegetable concentrate (alternatively fruit puree or vegetable puree orfruit pulp or vegetable pulp) can be dispersed in advance in thesuspension medium and thus diluted (step a)). In the other variant,fruit concentrate or vegetable concentrate can be used directly assuspension medium for the sterols and/or stanols, so and only thesterols and/or stanols are added to the concentrates, and the resultantdispersion can be comminuted and homogenized in the rotor-stator mill.Further additives listed in step a) are not then required.

The resultant formulations have a high content of sterols and/orstanols. They generally have a yield point, they are therefore solid,but may be liquefied again by shearing, so that they can be furtherprocessed by simple means directly in final food formulations.

The invention further relates, therefore, to fruit concentrates andvegetable concentrates which contain at least 1% by weight, preferablyat least 5% by weight, and particularly preferably at least 15% byweight, of sterols and/or stanols, based on the concentrates. Theseconcentrates have a water content of a maximum of 85% by weight,preferably a maximum of 75% by weight, and particularly preferably amaximum of 65%, in order to have the consistency which is advantageousfor further processing. The sterol particles and/or stanol particlespresent therein have a particle size distribution having a D_(90%) of amaximum of 50 μm, preferably a maximum of 40 μm, and particularlypreferably a maximum of 30 μm.

The invention further relates to food preparations which containsterol/stanol formulations of said composition. They are used preferablyin drinks and milk products which then contain 0.1 to 50% by weight,preferably 1 to 20% by weight, of the pulverulent coated preparationsbased on the total weight of the foods.

Sterol and/or Stanol

In the present invention, sterols obtained from plants and plant rawmaterials, termed phytosterols and phytostanols, are used. Knownexamples are ergosterol, brassicasterol, campesterol, avenasterol,desmosterol, clionasterol, stigmasterol, poriferasterol, chalinosterol,sitosterol and mixtures thereof, among these, use is preferably made ofβ-sitosterol and campesterol. Likewise, the hydrogenated saturated formsof the sterols, termed stanols, come under the compounds used, and herealso β-sitostanol and campesterol are preferred. As plant raw materialsources, there serve, inter alia, seeds and oils of soybeans, canola,palm kernels, corn, coconut, rape, sugarcane, sunflower, olive, cotton,soybean, peanut or products from tall oil production.

Protein-Containing Auxiliaries and/or Proteins

Protein-containing auxiliaries and proteins used are preferably milkpowder and/or whey powder and/or casein and/or caseinates. Milk powderssuch as commercially obtainable whole milk and skimmed milk powderswhich have been obtained from the respective milk quality grades bydrying are particularly suitable. They can be used in mixtures withother proteins or as sole support. If other proteins are added orproteins are used instead of milk powder as support, these are taken toinclude isolated proteins which are obtained from natural animal andplant sources and are added during production of the pulverulentpreparations. Possible sources of proteins are plants such as wheat,soybean, lupin, corn or sources of animal origin such as eggs or milk.

Skimmed milk powder, in the context of the present invention, isparticularly preferred since it has sufficient hydrophilizing propertieswithout therefore also simultaneously exhibiting the disadvantages ofsuch food emulsifiers described at the outset, which are otherwisecustomarily used especially for producing drinks and milk products,especially fermentation products such as yoghurt. In addition, skimmedmilk powder best masks the typical unpleasant sterol flavor andformulations having this additive have improved sensory propertiescompared with other auxiliaries.

Carbohydrates

The compounds used as carbohydrates comprise all polysaccharides andmonosaccharides which are suitable as foods, such as, for example,glucose, sucrose, fructose, trehalose, maltose, maltodextrin,cyclodextrin, invert sugar, palatinose, lactose, guar gum, xanthan,pectins, starch, starch derivatives and modified starch, alginates,carrageenan, wheat gluten and gum arabic. Preferably, use is made of gumarabic, galactomannans such as guar gum, xanthan, starch and starchderivatives and modified starches (OSA starch) as carbohydrate,particular preference is given to gum arabic.

Further Auxiliaries

As further auxiliaries, the preparations according to the invention cancontain antioxidants, preservatives and flow enhancers. Examples ofpossible antioxidants or preservatives are tocopherols, lecithins,ascorbic acid, parabens, butylated hydroxytoluene or butylatedhydroxyanisole, sorbic acid or benzoic acid and salts thereof.Preferably, tocopherols are used as antioxidants.

As flow regulator and improver, silicon dioxide can he used.

based on the total weight of the powders, with the proviso that they arefree from emulsifiers having a high surface activity selected from thegroup formed by lecithins, monoglycerides, diglycerides, polysorbates,sodium stearyllactylate, glycerol monostearate, lactic acid esters andpolyglycerol esters.

EXAMPLES Example 1

2400 g of deionized water were charged into the funnel of a Fryma mill(Fryma, Rheinfelden, type MZ 80 R, gap width: 240 μm), therein weredispersed 120 g of skimmed milk powder (spray dried skimmed milk powderADPI grade, supplier: Almil, Bad Homburg) and the dispersion washomogenized for circulation at 4U. 1800 g of sterol mixture (talloil/rape sterol 70/30, prills ˜2 mm) were added. The gap was slowlyclosed (minimal setting and the mixture was homogenized in circulationfor 30 min. In this case the temperature increased from 24° C. to 53° C.

One part of the resultant dispersion was dried in a vacuum at 60°/lmbar. Subsequently, the particle size distribution of the vacuum-driedpowder was measured by laser diffractometry (Beckman Coulter, type LS320). This gave a D_(90%) of 25 μm.

A further part was spray dried (APV Anhydro type 3 S spray drying system(2-fluid nozzle: 3 mm, Anhydro) temperature at the inlet: 185° C.,temperature at the outlet: 90° C., pressure 2 bar).

Example 2

2700 g of deionized water were charged into the funnel of a Fryma mill(Fryma Rheinfelden, type MZ 80 R, gap width: 240 μm), and therein weredispersed 138 g of gum arabic (total solids 94%) and the dispersion washomogenized in circulation at 4U. 2000 g of sterol mixture (talloil/rape sterol 70/30, prills ˜2 mm) were added. The gap was slowlyclosed (minimum setting) and the mixture was homogenized in circulationfor 30 min.

One part of the resultant dispersion was dried in a vacuum at 60°/lmbar, a further part was spray dried (APV Anhydro type 3 S spray-dryingsystem).

Subsequently, the particle size distribution of the vacuum-dried powderwas measured by laser diffractometry (Beckman Coulter, type LS 320).This gave a D_(90%) of 24 μm.

Example 3

Wet milling of sterols with coating and subsequent spray drying:

3055 g of water were charged at room temperature into the funnel of atoothed colloid mill (Fryma/type MZ 80 R). With the gap open (position0.9) the mill was started and 195 g of skimmed milk powder were addedand suspended and dissolved in circulation. 1750 g of phytosterol (talloil/rape sterol 70/30, prills 1-2 mm) were slowly added and mixed in.

The mill gap was gradually closed (end: position 0.0). At the endposition milling was continued for a further min in circulation.(Circulation pump throughput 5 l/min/final temperature 48° C.). Thethixotropic homogeneous dispersion obtained is subsequently spray dried(APV Anhdro type 3 S spray-drying system).

Example 4

Wet grinding of sterols in fruit pulp:

3440 g of mango puree (Döhler, water content 70%) were charged into thefunnel of a toothed colloid mill (Fryma/type MZ 80 R) at roomtemperature. With the gap open (position 0.9), the mill was started andthe mango puree was passed/milled in circulation. 640 g of phytosterol(tall oil/rape sterol 70/30, prills 1-2 mm) were slowly added and mixedin. The mill gap was gradually closed (end: position 0.0). At the endposition, milling was continued for a further 30 min in circulation.(Circulation pump throughput 3 l/min/final temperature 47° C.)

This resulted in a homogeneous fruit paste having a very finely groundsterol fraction. The product had a yield point, but became liquid againon shaking. The fruit paste is therefore outstandingly suitable forincorporation into cloudy fruit juices/fruit drinks. The sterol fractioncan be introduced without problem in this manner without the interferinghydrophobic properties of conventional sterol powders. The very finelyground sterol particles are not perceived optically in the fruit juice(no creaming/color difference). The mouth feel of the wet milled sterolparticles in the fruit juice is neutral, as was sought after.

Dispersion Test

The resultant powders were dispersed in milk and water in comparisonwith milled sterols of comparable particle size distribution. For this,approximately 250 ml of the liquid under test were placed in a glassbeaker and stirred (approximately 100 rpm). To the stirred liquid wereadded 2.5 g of the respective powder and the dispersion behavior wasassessed.

The coated sterol could be very readily dispersed in cold (15° C.) andhot (60° C.) water and also in milk (18° C.), whereas the untreatedsterol was dispersed poorly and owing to the hydrophobic surfaceremained on the liquid surface.

The sensory assessment found that the encapsulated sterols in water hada neutral taste and did not stick to gums and the oral cavity, whereasthe untreated powder stuck to the oral mucosa and, in addition to atypically adverse sterol taste, left an unpleasant sensory feeling.

The resultant powders are distinguished by improved free-flowingbehavior, improved stirrability into water and a higher bulk weightcompared with conventional finely ground sterols. The dried productshave a sterol content of greater than 90%. In Example 1, the sterolcontent of the dried powder is 93%. The powders may be introduced bysimple stirring into aqueous systems such as water, juices, milk etc.

The dispersions have a yield point, may be readily stirred and can headded simply to aqueous systems such as cold water, juices, milk etc.

What is claimed:
 1. A sterol- and/or stanol-containing powderformulation comprising free sterol particles and/or stanol particles;and an additive selected from the group consisting of proteins,protein-containing auxiliaries, carbohydrates, cellulose derivatives,sugar alcohols, fruit concentrates and vegetable concentrates, whereinin the powder formulation has a free sterol content of at least 75% byweight, and has a particle size distribution D_(90%), of less than orequal to 50 μm, said particles of the formulations in the form of apowder are readily wettable.
 2. The sterol- and/or stanol-containingpowder formulation of claim 1, wherein the additive comprises a proteinor a protein-containing auxiliary which is selected from the groupconsisting of milk powder, whey powder, casein, caseinates, andcombinations thereof.
 3. The sterol- and/or stanol-containing powderformulation of claim 1, wherein the additive comprises a carbohydratewhich is selected from the group of glucose, sucrose, fructose,trehalose, maltose, maltodextrin, cyclodextrin, invert sugar,palatinose, lactose, guar gum, xanthan, pectins, starch, starchderivatives, modified starches, alginates, carrageenan, wheat gluten,and gum arabic.
 4. The sterol- and/or stanol-containing powderformulation of claim 1, wherein the additive comprises gum arabic orskimmed milk powder.
 5. The sterol- and/or stanol-containing powderformulation of claim 1, wherein the weight ratio of additive tosterol/stanol fraction is in the range of 1:3 to 1:20.
 6. The sterol-and/or stanol-containing powder formulation of claim 1, wherein the freesterol/stanol content is greater than 85% by weight.
 7. The sterol-and/or stanol-containing powder formulation of claim 6, wherein the freesterol/stanol content is greater than 90% by weight.
 8. The sterol-and/or stanol-containing powder formulation of claim 1, wherein theformulation is free of a high surface activity emulsifier.
 9. A fruitconcentrate or vegetable concentrate comprising such an amount of thesterol- and/or stanol -containing powder formulation of claim 1, suchthat said concentrate comprises at least 1% by weight of the sterolsand/or stanols based on the total weight of said concentrate.
 10. A foodcontaining 0.1 to 50% by weight of the sterol- and/or stanol powderformulation of claim
 1. 11. A food containing 0.1 to 50% by weight ofthe fruit concentrate or vegetable concentrate of claim 9.